It is a well established practice in underground mining work, such as coal mining, tunnel excavation, or the like, to reinforce the roof of the mine to prevent its collapse. There are various types of reinforcement apparatus, the most common are of the mining bolt type. Various designs of ming bolts are known.
Split-Set® by Ingersoll-Rand is a mining bolt which is comprised of a c-shaped metal member which is forced into a bore hole and supports the rock by friction. The hollow shape of the Split-Set® bolt allows the bolt to deform rather than break when a rock shift occurs.
Swellex® by Atlas Copco, Inc. of Sweden is a hollow folded c-shaped tube which hydrostatically expands in the bore hole by means of high pressure water. During the swelling process, the Swellex® bolt adapts to fit the irregularities of the bore hole. The hollow shape allows the tube to deform during rock shifts. Unfortunately, the complex shape of the Swellex® mining bolt is expensive to manufacture. Further, the necessary high pressure water tools and fittings add to the expense and complexity of the method.
Spin-Lock® by Williams Co. discloses a rock bolt which has a hollow interior and has open ends for allowing grout to be pumped therethrough. No resin cartridges are disclosed.
Despite these developments, there exists a need for improved mining bolts and methods of use thereof.